为了满足快速、准确地进行大跨度桥梁安全性能评估的需要,提出了一种利用健康监测系统的动力监测数据评价预应力混凝土连续刚构桥的长期安全性能的方法.介绍了一座大跨度连续刚构桥健康监测系统动力测试的基本情况,并比较了环境振动测试和健康监测系统动力测试的结果.利用连续刚构桥的自振频率温度修正模型,采用考虑温度效应的实测动力特性对连续刚构桥有限元模型进行修正,得到反映实际状态的基准有限元模型,通过汽车荷载试验的结果验证该计算结果的准确性.最后,根据基准有限元模型的计算结果与设计计算结果的比较评估桥梁当前的安全性能.结果表明:根据长期动力特性监测结果修正的基准有限元模型能够反应桥梁实际工作状态,评估结果具有很好的精度,可以有效地应用于大跨度桥梁长期安全性能评估.
In order to meet the fast and accurate safety assessment requirement of long span bridges, a safety assessment method for long - term work performance of continuous long span rigid - frame bridg- es exploiting dynamic monitoring data taken from health monitoring system was present. The basic con- dition of dynamic monitoring system was introduced, and its availability was verified by field vibration test. The base finite element model of the continuous rigid frame bridge was established by finite ele- ment model updating with test modal characteristics in consideration of temperature' s influence using temperature modified frequencies calculated formula. The static calculation simulated truck load test was carried out and the results were confirmed by the test results from field load test. Finally, the safe- ty performance of the bridge was evaluated by comparison between the calculating static results from the base finite element model and the test ones. The conclusion shows that the baseline finite element model established based on long- te~n dynamic characteristics data can reflect the real work situation of the bridge, and the evaluation results have a good phed in the long- term safety performance evaluation precision, so this method can be effectively ap- of long span bridges.